/Engine/Source/Editor/Sequencer/Public/IKeyArea.h
Get all key handles that exist within the given time range
void GetKeyHandles ( [TArray](API\Runtime\Core\Containers\TArray)< [FKeyHandle](API\Runtime\Engine\Curves\FKeyHandle) > & OutHandles, const [TRange](API\Runtime\Core\Math\TRange)< [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) > & WithinRange ) const